Cookbook:Blueberry

The blueberry, sometimes known specifically as the American blueberry, is a small sweet fruit from the plant Vaccinium sect. Cyanococcus. It is similar to but distinct from the bilberry, which is sometimes known as the "European blueberry".

Characteristics
Blueberries are round and blue in color, with a light powdery coating and a small, star-shaped indentation opposite the stem end. Commercially available blueberries include larger berries, and smaller "wild" blueberries. The insides are sweet and light green in color, but when mashed the berries are purple and juicy. They also tend to change color during cooking. Acids, like lemon juice and vinegar, make blueberries redder, while in an alkaline environment, such as a batter with too much baking soda, the blueberries may turn greenish-blue.

Seasonality
Blueberries become available halfway through spring, with a peak in the summer. The North American blueberry harvest (responsible for most of the world's supply) runs from mid-April through early October, with peak harvest from mid-May to August. Fresh blueberries are available for nearly eight months of the year from producers across the United States and Canada, and they are typically available frozen throughout the year.

Selection and storage
Blueberries must be ripe when purchased, as they do not continue to ripen after harvesting. They should be completely blue (deep-purple blue to blue-black) with no tinge of red; reddish berries aren't ripe but can be used in cooking. Fresh blueberries should be firm, dry, plump, and smooth-skinned, with no overly soft spots. Soft, watery fruit means the berries are overripe; dehydrated, wrinkled fruit means the berries have been stored too long.

Blueberries tend to last longer than other berry varieties, but they should still be stored like other berries as they are very perishable. As such, keep them refrigerated in a rigid covered container, and do not wash them until right before use to prevent molding. They should last up to two weeks if they are freshly picked. For longer storage, keep in an airtight container and store in the freezer.

Use
Blueberries may be eaten raw or processed in various ways. Like other berries, they can be folded into batters, made into preserves, used as garnishes, incorporated into custards, and more.

When using blueberries in batter, add them last and stir gently to reduce color streaking. If frozen, do not thaw before use, since they tend to release their juice upon thaw. When making pancakes and waffles, add the blueberries as soon as the batter has been poured on the griddle or waffle iron. This will make the pancakes prettier, and they'll be easier to flip. If frozen blueberries are used, cooking time may have to be increased to be sure the berries are heated through.